Liquid detergent and cleaning agent composition

ABSTRACT

The invention relates to liquid detergent and cleaning agent compositions of high storage stability. They comprise a liquid medium with a water content of up to 15 wt. % and particulate coating bleaching agents suspended therein. The bleaching agent has a dissolving time of at least 5 minutes and a coating of at least two layers: The innermost layer comprises one or more hydrate-forming inorganic salts as the main component(s), and an outer layer, which makes up 0.2 to 5 wt. % of the coated bleaching agent, comprises alkali metal silicate(s) with a modulus of SiO 2  to M 2 O (M=alkali metal) of greater than 2.5 as the main component(s). Preferred compositions comprise sodium percarbonate with an innermost layer of substantially sodium sulfate and an outermost layer of substantially 0.5 to 1.5 wt. % sodium silicate (modulus 3.2 to 4.2) as the bleaching agent.

The invention relates to a liquid detergent and cleaning agentcomposition comprising a liquid medium with a water content of up to 15wt. % and particulate coated bleaching agents suspended in the liquidmedium.

Although detergents and cleaning compositions comprising bleachingagents are usually used in powder or granule form, there is an interestin also marketing and using such products in the liquid form.

GB Patent 1 303 810 discloses pourable, liquid compositions for cleaningand rinsing purposes which comprise a clear liquid medium and one ormore particulate components suspended therein. The liquid medium, whichcan be aqueous or non-aqueous, comprises one or more cleaning-activecomponents, such as anionic, nonionic or cationic surfactants directedtowards the intended use. The material suspended in the liquid mediumexpediently comprises those components which produce a specifictechnical effect in the composition. Examples which are mentioned inthis document are bleaching agents, enzymes and perfumes, it beingpossible for these substances to be surrounded by a coating which servesto avoid an interaction with the liquid medium. A cleaning compositionof the generic type comprises a bleaching-active chlorine compound, thatis to say a sodium hypochlorite solution, encapsulated in a polyethylenewax. The compositions of the generic type additionally comprisesubstances to adjust the rheological properties, as a result of whichthe particulate constituents are kept in a stable suspension in theliquid medium.

GB 1,303,810 A1 gives no indication of whether and in what form sodiumpercarbonate, which is known to be not very stable in the presence ofmoisture, and therefore a high loss of active oxygen must be expectedduring storage in a liquid detergent comprising water, can beincorporated into a liquid detergent and cleaning composition.

WO 01/66685 A1 discloses non-aqueous liquid detergent and cleaningcompositions which are characterized by the presence of liquid bleachingactivators. “Non-aqueous” is understood as meaning a content of freewater of less than 5 wt. %, in particular less than 2 wt. %. Thecompositions can also comprise dispersed bleaching agents. Sodiumperborates, sodium percarbonate, persulfates, peroxypyrophosphates andalkyl and aryl peroxy acids, inter alia, are mentioned. The bleachingagents can also be coated, but no specific coatings are mentioned. Thecompositions of the examples comprise neither sodium percarbonate nor acoated sodium percarbonate. The problem of the loss of active oxygen dueto the water present during storage of such compositions comprisingbleaching agents is not referred to.

WO 02/057402 A1 discloses washing- and cleaning-active liquidcompositions which comprise a transparent. or translucent liquid mediumand solid particles, the liquid medium comprising less than 10 wt. % ofwater and the composition being packaged in ready-for-use portions inbags of a transparent or translucent water-soluble material. The liquidmedium comprises, in particular, anionic and/or nonionic surfactants,water-soluble builders and additionally solvents, such as alcohols. Thesolid particles are, in particular, bleaching agents, bleachingactivators and enzymes. Among the bleaching-active components, alkalimetal percarbonates, in particular sodium percarbonate, are mentioned.Such substances are expediently used in granule form, and in particularin a coated form, where the coating material can include one or moreinorganic salts, such as alkali metal silicates and carbonate and boratesalts, or organic materials, such as waxes, oils and soaps.

An essential feature of the compositions according to WO 02/057402 A1 isthat both the liquid medium and the bag are transparent or translucent.For reasons of better marketing, it has since been acknowledged that itwould be more advantageous if the bag and/or the medium were opaque,since the customer could regard the suspended material as a disadvantageand/or associate it with an undesirable change in quality.

The document acknowledged above contains no example of a detergent whichcomprises a particulate bleaching agent, such as sodium percarbonate.The document also does not show what criteria a coating of sodiumpercarbonate must fulfill in order to ensure in a water-containingliquid detergent or cleaning composition on the one hand an adequatestorage stability, but on the other hand a good activity during thewashing or cleaning process.

It is indeed known from the abovementioned WO specification and otherdocuments that the storage stability of sodium percarbonate in a dampwarm environment can be improved by application of a single- ormultilayered coating, one coating material also being an alkali metalsilicate, but the products known to date have proved to be unsuitablefor use in liquid detergent and cleaning compositions in one or otheraspect, in particular in respect of their storage stability and releaseof the bleaching agent in a manner appropriate for the use.

It is indeed known that by application of a coating layer ofsubstantially alkali metal silicate to sodium percarbonate particles therelease of the sodium percarbonate in an aqueous environment can bedelayed, but large amounts of coating are necessary for an adequatedelay, which in their turn adversely impair the washing activity, sincethe alkali metal silicate is not dissolved satisfactorily in the washliquor and the “coatings” can therefore be deposited on the laundry asgrey tinge. Such undissolved constituents can also lead to undesirabledeposits in the washing machine.

The doctrine of EP 0 623 553 A1 is that the dissolving time of sodiumpercarbonate which has a coating layer of 1.5 wt. % sodium silicate is3.5 minutes. An increase in the coating layer to 12.5 wt. % indeed leadsto a prolonging of the dissolving time to about 9 minutes, but a sodiumpercarbonate coated in this way proved to be unsuitable in a liquiddetergent with about 5 wt. % water, because too high a loss of activeoxygen occurred during storage. According to EP 0 992 575 A1 thedissolving time of sodium percarbonate can indeed be increased furtherby using an alkali metal silicate with a modulus of greater than 3 to 5for the coating and employing it in a correspondingly high amount, butthe products obtained in this way lead to the grey tinge alreadymentioned.

The object of the present invention accordingly is to provide a liquiddetergent and cleaning agent composition which comprises a liquid mediumwith a water content of up to 15 wt. %, in particular 3 to 10 wt. %,based on the composition, and one or more particulate coated bleachingagents suspended in the liquid medium, in particular coated sodiumpercarbonate, which has an adequate storage stability with asimultaneously high bleaching activity.

According to a further object of the invention, the particulate coatedbleaching agents contained in the composition, such as, in particular,coated sodium percarbonate, should have such a coating which leads to nogrey tinge during use as a detergent.

According to a further object of the invention, such compositions shouldbe provided which additionally comprise, in addition to a particulatecoated bleaching agent based on an inorganic peroxy compound, activatorswhich also display their action in full after a relatively long storagetime and dissolve the peroxy compound and the activator at about thesame speed during the washing or cleaning process and are thereforecapable of the formation of a peroxycarboxylic acid.

According to further objects, such compositions in which it cannot beseen visually that they comprise a suspended material should beprovided.

The abovementioned objects and further objects such as are deduced fromthe following description are achieved by the compositions according tothe invention.

A liquid detergent and cleaning agent composition comprising a liquidmedium with a water content of up to 15 wt. %, based on the composition,and one or more particulate coated bleaching agents, suspended in theliquid medium, from the series consisting of inorganic and organicperoxy compounds has been found, characterized in that the bleachingagent has a coating of at least two layers, wherein an innermost layer,which makes up 2 to 20 wt. % of the coated bleaching agent, comprisesone or more hydrate-forming inorganic salts as the main component(s),and an outer layer, which makes up 0.2 to 5 wt. %, in particular 0.2 toless than 3 wt. % of the coated bleaching agent, comprises alkali metalsilicate(s) with a modulus of SiO₂ to M₂O (M=alkali metal) of greaterthan 2.5 as the main component(s), and wherein the coated bleachingagent has a dissolving time of at least 5 minutes (measured for 95%dissolution in water at 15° C. and 2 g/l).

The composition conventionally comprises at least such an amount ofwater as is present as a secondary constituent in the startingsubstances, that is to say at least about 0.5 wt. %. The water can be inthe free form and/or a weakly bonded form. The amount stated is thatwhich can be detected by means of Karl Fischer titration.

The subclaims relate to preferred embodiments of the composition,particularly preferred compositions comprising a sodium percarbonatecoated according to the invention as the bleaching agent. Finally, afurther subclaim relates to a composition of the generic type, which ispackaged in portioned form in bags of a water-soluble polymeric materialwhich are suitable for washing and cleaning purposes.

It has been found that liquid detergent and cleaning agent compositionsaccording to the invention with a two-layered coating, according to theclaims, on the particulate bleaching agent both have the storagestability desired in practice and also substantially avoid the problemof greying of the laundry because of the specific choice and embodimentof the coating. Surprisingly, it is even possible to use in thedetergent and cleaning agent compositions according to the inventionsuch coated bleaching agents in which the total amount of coating makesup less than 10 wt. %, based on the coated bleaching agent.

It has been found that the dissolving time of the coated bleaching agentin water—95% dissolution at 15° C. at a use concentration of 2 g/l—is animportant choice criterion for the suitability of a coated bleachingagent for liquid detergent and cleaning compositions. The dissolvingtime is expediently more than 5 minutes, in particular more than 10minutes and in particular in the range from 15 to 30 minutes. However,the dissolving time is not the only choice criterion, but the residualactive oxygen content in a water-containing detergent test recipe afteran appropriate storage time must additionally be determined. Theresidual active oxygen content of a composition according to theinvention comprising 10 wt. % active oxygen component—the compositionused for test purposes is stated in the examples part—after storage for4 weeks in closed PE vessels at 35° C. is expediently more than 50% andpreferably more than 60%, particularly preferably about/more than 70%.

The compositions according to the invention can comprise one or moreinorganic and/or organic peroxy compounds. The inorganic peroxycompounds are, in particular, such compounds which liberate hydrogenperoxide on dissolving in water. Examples of these are percarbonates,perborates, perphosphates, persulfates and persilicates, preferablyalkali metal salts and particularly preferably sodium salts of thesesubstance classes. Sodium percarbonate of the general formula2Na₂CO₃.3H₂O₂ is particularly preferred.

According to an alternative embodiment, the composition comprises as thebleaching agent a coated organic peroxy compound, this being, inparticular, an aromatic or aliphatic peroxycarboxylic acid which hasone, two or more peroxy groups and is solid at room temperature. Peroxyacids having at least 6 carbon atoms, in particular 6 to 18 carbonatoms, are preferred. Examples of aliphatic peroxy acids with one peroxygroup are peroxylauric acid, peroxystearic acid andphthalimidoperoxycaproic acid. Aromatic peroxy acids with one or twoperoxy groups, such as peroxyphthalic acid, peroxyisophthalic acid,diperoxyphthalic acid and diperoxyisophthalic acid, are alsoparticularly suitable. Among the aliphatic peroxy acids with two peroxygroups, linear diperoxydicarboxylic acids, such asn-hexanediperoxydicarboxylic acid, n-octanediperoxydicarboxylic acid andn-dodecanediperoxydicarboxylic acid, are mentioned by way of example.2-(C₁ to C₁₂)alkyldiperoxysuccinic acids, such as2-n-decyldiperoxybutane-1,4-dioic acid, can also be employed. Diacylperoxides are also active. It is a particular advantage of the inventionthat the coating according to the invention with a hydrate-forming saltas the innermost layer leads to a very good desensitization of theperoxy compound, so that no undesirable interactions occur between theorganic peroxy compound and constituents in the liquid medium which arecapable of oxidation. In the case of the more sparingly water-solubleorganic peroxycarboxylic acids, the solubility-prolonging second layercan be omitted. The single-layered coating with a hydrate-forming saltis then sufficient.

The amount of coating of the innermost layer is conventionally in therange from 2 to 20 wt. %, based on the coated bleaching agent, but inprinciple the amount of coating could also be increased if this isdesired. In practice, an amount of coating of the innermost layer in therange from 2 to 10 wt. %, in particular 3 to 7 wt. %, is sufficient toensure an adequate stabilization in combination with one or more outercoating layers. The innermost coating layer can comprise one or morehydrate-forming inorganic salts, these preferably being salts from theseries consisting of alkali metal sulfates, magnesium sulfate, alkalimetal carbonates, alkali metal bicarbonates, mixed salts of alkali metalbicarbonate and/or alkali metal carbonate, such as sodiumsesquicarbonate and [Na₂SO₄(Na₃CO₃)_(n)], alkali metal borates andalkali metal perborates. The innermost layer can additionally alsocomprise, in addition to one or more hydrate-forming inorganic salts,further compounds having a stabilizing action, such as alkali metalsalts of carboxylic acids or hydroxycarboxylic acids. As mentionedabove, these salts are particularly preferably sodium salts. Thebleaching agent particularly preferably comprises as the innermostcoating layer such a one of substantially sodium sulfate. Theabovementioned coating amounts are in each case per cent by weight,based on the coated bleaching agent, the coating material having beencalculated as hydrate-free.

On the innermost coating layer lie one or more outer coating layers, oneof these coating layers comprising alkali metal silicate(s) with amodulus of greater than 2.5, preferably 3 to 5 and particularlypreferably 3.2 to 4.2 as the main component(s). The modulus stated forthe alkali metal silicate contained as the main component in an outercoating layer is that modulus which the alkali metal silicate solutionwhich was employed for the preparation of the corresponding coatinglayer had. The term “outer coating layer comprising alkali metalsilicate” means either the outermost coating layer of a coating on thesodium percarbonate particles comprising at least two layers or acoating layer which in its turn can be covered by and can cover one ormore layers.

Preferred compositions comprise coated sodium percarbonate particles,which can have been produced by any desired preparation process and cancomprise stabilizers which are known per se, such as magnesium salts,silicates and phosphates.

In the crystallization process for the preparation of the sodiumpercarbonate core, hydrogen peroxide and sodium carbonate are reacted inan aqueous phase in the presence or in the absence of a salting outagent to give sodium percarbonate and the latter is separated off fromthe mother liquor. In the process by fluidized bed spray granulation, anaqueous hydrogen peroxide solution and an aqueous soda solution aresprayed on to sodium percarbonate seeds, which are in a fluidized bed,and at the same time water is evaporated. Finally, sodium percarbonatecan also be obtained by bringing solid soda or a hydrate thereof intocontact with an aqueous hydrogen peroxide solution and drying.

In respect of a high internal stability of the sodium percarbonate corein the presence of detergent constituents, it is particularly expedientif the average particle diameter is greater than 0.5 mm, andparticularly preferably in the range from 0.5 to 1 mm. The particlespectrum expediently contains substantially no particles smaller than0.2 mm.

The content of particles with a diameter of less than 0.4 mm ispreferably less than 10 wt. %, particularly preferably less than 5 wt.%.

The diameter of the sodium percarbonate particles which are coated withat least two layers is only slightly greater than that of the sodiumpercarbonate core. In general, the thickness of the total coating of thesodium percarbonate core is less than 20 μm. The layer thickness of thelayers, of which there are at least two, is preferably in the range from2 to 15 μm, in particular 4 to 10 μm. Since the amount of the innermostcoating layer of the sodium percarbonate particles coated according tothe invention as a rule makes up a significantly greater proportion thanthe outer layer comprising alkali metal silicate, the thickness of theinnermost layer is as a rule also greater than that of the outer layercomprising alkali metal silicate.

Although in the description individual layers are referred to,analogously to in the prior art, it should be noted that theconstituents of the layers lying on top of one another can pass into oneanother at least in the boundary region. This at least partialpenetration results from the fact that in the case of the particle ofthe peroxy compound or the particle of the peroxy compound which have acoating layer, the surface is partly superficially dissolved by using anaqueous coating composition solution.

The coating of the inorganic and organic peroxy compounds is carried outin a manner known per se. In principle, the particles to be coated arebrought into contact once or several times, as uniformly as possible,with a solution containing one or more coating components, and are driedat the same time or subsequently. For example, the bringing into contactcan be effected on a granulating plate or in a mixer, such as a tumblemixer. The coating is particularly preferably carried out by fluidizedbed coating, wherein a first solution containing the coatingcomponent(s) for formation of an innermost layer and then a secondsolution containing the coating component(s) for formation of an outerlayer are sprayed on to the peroxy compound or peroxy compound coatedwith one or more layers, which is in a fluidized bed, and are dried atthe same time with the fluidized bed gas. The fluidized bed gas can beany desired gas, in particular air, air heated directly with acombustion gas and with a CO₂ content in the range from, for example,0.1 to about 15%, pure CO₂, nitrogen and inert gases. Reference is madeto the documents acknowledged in the introduction for a detaileddescription of fluidized bed coating.

According to a particularly preferred embodiment, the innermost coatinglayer substantially comprises sodium sulfate, which can also be presentin part in the hydrated form. The term “substantially” is understood asmeaning that sodium bicarbonate or a double salt of sodium bicarbonate,such as sesquicarbonate or Wegscheider salt, can also be contained atleast in the boundary layer between the sodium percarbonate core and theinnermost layer.

The outer coating layer comprising alkali metal silicates is preferablysuch a one of sodium silicate which has been obtained by coating aperoxy compound having an innermost coating layer using a sodiumwater-glass solution with a modulus according to the claims. If theinnermost coating layer comprises constituents which have an alkalineaction, such as sodium carbonate, the modulus on an alkali metalsilicate layer on the innermost coating layer can become somewhat lowerand therefore shorten the dissolving time, since interactions betweenthe constituents of the coating layers cannot be ruled out at least inthe boundary region. If the coating layer comprising alkali metalsilicate is produced by fluidized bed coating, wherein a gas comprisingCO₂ is used as the fluidized bed gas or driving gas, a lowering of thepH may occur, on the other hand, resulting in an increase in the modulusand therefore an increase in the dissolving time.

In a particularly preferred embodiment of the invention, the compositioncomprises a peroxy compound coated with at least two layers, wherein thelayer comprising alkali metal silicate has been prepared using anaqueous alkali metal silicate solution with a concentration of equal toor less than 20 wt. %, preferably about 5 to 10 wt. %. With a specifiedamount of alkali metal silicate and a specified modulus in the coating,in fact, the dissolving time can be increased by lowering the useconcentration of alkali metal silicate in the solution. It is possiblein this manner to obtain, with a considerably lower amount of alkalimetal silicate, peroxy compounds which have a sufficiently stablecoating and reduce or avoid the known greying problem in a liquiddetergent composition. By lowering the alkali metal silicateconcentration in the spray solution used for the coating it is possibleto lower the amount of alkali metal silicate in the coating to valuesbelow 3 wt. %, and preferably to values in the range from 0.5 to 1.5 wt.%. Surprisingly, such products have a high storage stability inwater-containing liquid detergents and nevertheless dissolvesufficiently rapidly to be able to liberate the active oxygen at thecorrect point in time.

Further details of the preparation and composition of the particularlypreferred sodium percarbonate particles coated with at least two layerscan be found in DE 102 61 161.0, the full content of the disclosure ofwhich is included in this Application.

The liquid detergent, bleaching agent and cleaning agent compositionsaccording to the invention comprise one or more peroxy compounds coatedaccording to the invention in an amount in the range from 1 to 80 wt. %,preferably 2 to 50 wt. %, detergents preferably comprising about 5 to 25wt. % of coated bleaching agent. The dissolving time of the coatingbleaching agent contained in this composition under test conditions at15° C. is preferably in the range from 15 to 60 minutes. Particularlypreferably 15 to 30 minutes.

Compositions according to the invention comprise one or more activecomponents with a surfactant character, in particular in the liquidmedium. The amount of such substances employed can be in wide ranges,conventionally in the range from 15 to 70 wt. %, preferably 20 to 60 wt.%. Although the surfactant system can be, in particular, anionicsurfactants or-nonionic surfactants, preferred compositions compriseboth anionic and nonionic surfactants, preferably in the range from 1:2to 2:1.

The anionic surfactants are, in particular, those from the seriesconsisting of anionic sulfonates, which include sulfonic acids and saltsthereof. Examples are C₅-C₂₀-, preferably C₁₀-C₁₆-alkylbenzenesulfonatesand alkyl ether-sulfonates, primary or secondary C₆-C₂₂-alkanesulfonatesand sulfonated polycarboxylic acids. Alkylbenzenesulfonates, inparticular those having 11 to 13 C atoms in the alkyl group, areparticularly preferred.

A further class of anionic surfactants comprises primary and secondaryalkyl sulfates with a linear or branched alkyl or alkenyl group having 9to 22 C atoms, in particular 12 to 18 C atoms, and salts thereof.Beta-branched alkyl sulfate surfactants and commercially availablemixtures comprising these are particularly * preferred. In addition,however, alkyl sulfates which are mono- or polysubstituted by alkyl inthe middle of the longest alkyl chain and have, in particular, 14-20 Catoms are also suitable. Examples of these are mono- anddimethyl-branched primary alkyl sulfates having preferably 14 to 16 Catoms in the longest linear chain.

The nonionic surfactants are, in particular, alkoxylated compounds, inparticular ethoxylated and propoxylated compounds. Nonionic condensatesof alkylphenols with ethylene oxide or propylene oxide, nonionicethoxylated alcohols and nonionic ethoxylated and/or propoxylated fattyalcohols are particularly suitable. Condensation products of fattyalcohols with 1 to 50 mol, preferably 1 to 10 mol of alkylene oxide areparticularly suitable. A further class of nonionic surfactants forcompositions according to the invention comprises polyhydroxy-fatty acidamides, wherein an organic radical with one or more hydroxyl groups,which can also be alkoxylated, is bonded to the amide nitrogen. Thisgroup is preferably a sugar radical.

The surfactant system in the liquid medium can also comprise a cationicsurfactant, in particular in such systems which comprise no anionicsurfactant. The cationic surfactants are, for example, mono- anddialkoxylated quaternary amines with a C6- to C₁₈-alkyl radical bondedto the nitrogen and one or two hydroxyalkyl groups.

Preferred liquid compositions according to the invention additionallycomprise builders dissolved in the liquid medium or suspended therein.The amount of builders employed can be in wide limits, and a content inthe range from 2 to 40 wt. % is preferred. Water-soluble builders are,in particular, monomeric carboxylic acids with one or more carboxylgroups, or homo- or copolymers containing carboxyl groups, and saltsthereof. The compositions particularly preferably comprise a C₁₂ toC₁₈-fatty acid or salt thereof. An amount employed in the range from 5to 20 wt. %, based on the composition, is particularly suitable.

Compositions according to the invention can also comprise builders basedon phosphates, such as, in particular, alkali metal tripolyphosphates,and based on alumosilicates, such as, in particular, zeolites and/orcrystalline layered silicates. The amount of alumosilicates employed isexpediently in the range from 5 to 50 wt. %.

According to a preferred embodiment, the compositions also comprise oneor more chelating compounds, in particular those with one or morephosphonate groups, in an amount of up to 15 wt. %, preferably up to 10wt. %.

The presence of such chelating agents has a favourable effect not onlyon the washing and cleaning action of the composition, but surprisinglyalso on the storage stability of a composition comprising alkali metalpercarbonate, in particular sodium percarbonate. Particularly suitablephosphonates are alkali metal salts ofethane-1-hydroxy-1,1-diphosphonate, nitrilotrimethylenephosphonate,diethylenetriamine-penta(methylenephosphonate),ethylenediamine-tetra(methylenephosphonate) andhexamethylenediamine-tetra(methylenephosphonate). Further chelatingagents are nitrilotriacetic acid and polyaminocarboxylic acids, such as,in particular, ethylenediaminetetraacetic acid,diethylenetriaminepentaacetic acid, ethylenediamine-N,N′-disuccinic acidand alkali metal and ammonium salts thereof. Finally, polybasiccarboxylic acids and, in particular, hydroxycarboxylic acids, such as,in particular, tartaric acid and citric acid, are suitable chelatingagents for compositions according to the invention.

The liquid medium comprises as the solvent up to 15 wt. % water,preferably 0.5 to 10 wt. % and particularly preferably 3 to 7 wt. %.

As a rule, organic solvents are additionally present as solubilizingagents, and among these, in particular, mono- or polyhydric alcoholshaving up to 6 C atoms which are liquid at room temperature. Thealcohols can additionally contain hydrophilic substituents, such as, inparticular, amino, ether and carboxyl groups. Examples of suitablealcohols are: methanol, ethanol, n-propanol, isopropanol, n-butanol,ethylene glycol, 1,3-propylene glycol, 1,3-propylene glycol,1,4-butylene glycol, glycerol, diethylene glycol, ethylene glycol methylether, ethanolamine, diethanolamine and triethanolamine. The organicsolvents are expediently present in an amount of less than 30 wt. %, inparticular less than 25 wt. %. The concrete amount employed of the oneor more organic solvents depends on the solubility of the componentscontained in the liquid medium, on the effects specifically desired,such as a pH adjustment by alkanolamines, and for adjustment of theviscosity of the liquid medium.

The liquid compositions according to the invention expediently compriseagents for adjustment of the rheological properties, in order on the onehand to impart the desired viscosity to the composition and on the otherhand to keep the insoluble constituents dispersed in the composition inthe dispersed form. Examples of agents for adjusting the rheologicalproperties are suspension auxiliaries, such as swelling clays, inparticular montmorillonites, precipitated and pyrogenic silicas,vegetable gum, in particular xanthans, and polymeric gelling agents,such as vinyl polymers containing carboxyl groups.

The liquid medium can additionally comprise conventional auxiliarysubstances for detergents and cleaning compositions, and among thesefragrances, dyestuffs, optical brighteners, foam inhibitors,disinfectants and agents for regulating the pH. A further classcomprises plasticizers based on hydrophilic and organophilic clays.

According to a further preferred embodiment, the compositions compriseone or more so-called activators, which are understood as meaningprecursors of peroxycarboxylic acids. Under the washing and cleaningconditions peroxycarboxylic acids, which have both a good bleaching anda disinfecting action, are formed in situ from these activators and thehydrogen peroxide liberated during the dissolving of an inorganic peroxycompound, such as, in particular, sodium percarbonate. Both hydrophobicand hydrophilic activators are used, so that these can be present bothdissolved in the liquid medium and/or suspended in this. The activatorsare, in particular, N- and O-acylated compounds. Nitriles, in particularamino-functionalized nitrites and salts thereof (nitrile-quats), canfurthermore be employed as activators. Typical representatives are to befound e.g. in the journal Tenside Surf. Det. 1997, 34(6), pages 404-409.

Suitable classes of activators include anhydrides, esters, imides andoximes. Examples of 0-acylated activators are glycerol triacetate,triethyl acetylcitrate, ethylene glycol diacetate,2,5-diacetoxy-2,5-dihydrofuran and alkanoyloxybenzenesulfonates, such asisomeric trimethylhexanoyloxybenzenesulfonates, sodiumnonanoyloxy-benzenesulfonate (NOBS), benzoyloxybenzenesulfonate andnonanoyl-6-aminocaproyloxybenzenesulfonate.

Among the N-acyl compounds there may be mentioned in particularsubstances with an amide structure and substances with an imidestructure, examples are N,N,N′,N′-tetraacylated alkylenediamines, suchas, in particular, tetraacetylethylenediamine (TAED), N-acyllactams,N-benzoyl-substituted ureas, N-acylsuccinimides and N-acylatedimidazoles. In the N-acylated lactams, the lactam ring contains, inparticular, 4 to 8 C atoms and the acyl group bonded to the lactamnitrogen 2 to 12, in particular 6 to 12 C atoms. The lactam ring systemis, in particular, valerolactam and caprolactam. In activators based onN-acyl-imidazoles and N-acyl-pyrrolidones, benzoyl is a preferred acylgroup. Activators of the following general formulaeR¹—C(O)—NR⁵—R²—C(O)-L or R¹—NR—C(O)—R²—C(O)-L, the specific meaning ofwhich can be found in EP 0 170 386 A1, can also be employed.

According to a specific embodiment, the composition according to theinvention comprises both an inorganic peroxy compound which liberateshydrogen peroxide, in particular sodium percarbonate coated according tothe invention, and an activator. Depending on the desired substanceproperties, the activator can be liquid or solid. Solid activators canbe coated or non-coated. Coating of the activator is expedient if thishas an inadequate stability in the liquid medium during storage of thecomposition or, if used in too early a stage, loses its action as aprecursor for the formation of a peroxycarboxylic acid, for example byhydrolysis. By application of a single- or multi-stage coating, inparticular one such as the peroxy compound has, it is possible tocoordinate the dissolving time of the peroxy compound and of theactivator to one another. Such a coordination of the dissolving time isof advantage in particular if the system additionally comprises enzymes,which expediently display their full activity before they aredeactivated by liberation of the peroxy compound and therefore, inparticular, hydrogen peroxide and a peroxycarboxylic acid formed fromthe activator and hydrogen peroxide.

The composition can additionally comprise conventional washing- andcleaning-active enzymes, in particular lipases, cutinases, amylases,neutral and alkaline proteases, esterases, cellulases, pectinases,lactases and peroxidases.

The liquid detergent and cleaning agent compositions can have boththixotropic, pseudoplastic and shear thinning rheological properties.Thixotropic and pseudoplastic compositions are preferred.

According to a further preferred embodiment of the composition accordingto the invention, this is packaged in portioned form in bags of awater-soluble polymeric material which are suitable for washing andcleaning purposes. In respect of the material of the bags and in respectof further details of the constituents of the detergent and cleaningcomposition, reference is made to WO 02/057402 A1, the disclosurecontent of which is included in the present Application. Compositionsaccording to the invention which are not transparent can comprise anactive amount of at least one opacifying agent which is not soluble inthe formulation to give a clear solution and thus ensures opacity.Suitable opacifying agents for the purpose mentioned are commerciallyavailable products from the series consisting of styrene-acrylatecopolymers (e.g. Acusol® Opacifier from Rohm & Haas Co.).

Silicone-quats which contain at least one organic radical with aquaternary ammonium group bonded to Si directly or via an O bridge on apolysiloxane chain, in particular polydimethylsiloxane chain, can alsobe employed as opacifying agents. The organic radical is, for example,such a one of the general structure -Q-N^(⊕)(CH₃)₂—R; Q represents abridge member having 2 to 6 C atoms, which can also contain one or moresubstituents, such as OH, and R represents alkyl having 1 to 18, inparticular 1 to 3 C atoms, wherein R represents alkyl which can besubstituted internally or terminally, for example by OH, Cl, NH₂, COOH,OCH₃ or (C₂-C₁₈)acyl-NH. Silicone-quats are commercially obtainable(Rewoquat®SQ from Degussa AG).

An amount employed in the range from 0.1 to 3 wt. %, in particular 0.5to 2 wt. %, is sufficient already to obtain a composition which iscompletely opaque in a thin layer (approx. 5-10 mm).

The invention is illustrated further with the aid of the followingexamples. The experiments show the unexpected effect of the increase instability with a simultaneously appropriate dissolving time of theinorganic bleaching components in a detergent composition.

EXAMPLES

a) Preparation of Coated Bleaching Agent

Sodium percarbonate coated with two layers was prepared by coatingsodium percarbonate in a fluidized bed, the first layer substantiallycomprising sodium sulfate and the second layer comprising substantiallysodium silicates. Details of the preparation and variation are to befound in DE 102 61 161.0.

In the examples, a commercially available sodium percarbonate coatedwith 6 wt. % sodium sulfate was employed as the starting material,namely Q30 and Q35 from Degussa, which differ only in the grainspectrum, Q35 being coarser than Q30 (Q30: D₅₀=0.55 mm, Q35: D₅₀=0.70mm)

Q30 or Q35 was coated in a fluidized bed coating unit using awater-glass solution. Spraying was carried out at a fluidized bedtemperature of about 60° C. Air served as the fluidized bed gas at anintake temperature in the region of about 100° C. After the spraying thefeed air temperature was lowered somewhat and after-drying was carriedout at a fluidized bed temperature of 85° C. The concentration of thewater-glass solution, the modulus, the coating amount and the dissolvingtime in water, measured at 2 g/l, at 15° C. by conductometric monitoringat up to 95% dissolution, follow from table 2.

b) Determination of the Stability

The sodium percarbonate coated with two layers was added in an amount of10 wt. % to a liquid base recipe comprising washing- and cleaning-activecomponents, the mixture was mixed homogeneously and the liquid mixturewas stored at 35° C. in PE drums for up to 4 weeks. To determine theactive oxygen, the total contents of each drum were dissolved completelyand the Oa content was determined iodometrically. The Oa contents at thestart and after 2 and 4 weeks and the residual Oa contents (relative tothe starting Oa) follow from the table.

In further experiments, a phosphate stabilizer was additionally added tothe composition—0.5% ethylenediaminetetramethylenephosphonate (EDTMP).It was possible to increase the storage stability further by means ofthe stabilizer. TABLE 1 Base recipe (1,000 g batch) Amount (g)Constituents 97.4 Monoethanolamine 40.0 Water 36.6 Ethanol 161.4Phenoxyethanol 235.6 C₁₃-C₁₅-Fatty alcohol polyglycol ether (4EO) 258.0Dodecylbenzenesulfonate 172.0 Coconut fatty acid

TABLE 2 Storage stability of sodium percarbonate coated with two layersin a liquid detergent % Oa after storage Residual Oa Residual Oa CoatingDissolving at 35° C. after 4 w after 4 w with 1st layer: Na₂SO₄ timeafter x weeks (w) without stabilizer EDTMP stabilizer Ex. No. 2nd layer:as stated **) (min) Start 2 w 4 w (% rel) (% rel) CE1 Q30 *) 1.5 13.58 7.20 3.77 28 55 E1 Q30/2% Wg 2.0 10 13.51  7.32 4.30 32 E2 Q30/1% Wg3.2 12 13.48 10.53 8.23 61 E3 Q30/3% Wg 3.2 59 13.21 12.00 11.26 85 89E4 Q30/5% Wg 3.2 71 13.28 11.98 11.20 84 E5 ***) Q35/0.75% Wg 3.2 13.4610.38 8.46 63 67 E6 ***) Q35/0.75% Wg 3.2 12.7 13.29 11.55 9.95 75 E7Q35/1.5% Wg 3.3 35 12.95 11.96 11.26 87 E8 Q35/1.5% Wg 4.0 60 13.2411.92 11.24 85 E9 Q35/0.75% Wg 3.4# 14.8 13.34 11.73 10.67 80 E10Q35/0.75% Wg 3.4# 19.6 13.33 12.10 11.29 85 E11 Q30/0.75% Wg 3.2## 8.313.50 12.14 11.29 84 E12 Q30/1.5% Wg 3.2## 36 13.35 12.62 12.16 91*) Q30 = Sodium percarbonate with 6% Na₂SO₄ in a single coating layerQ35 = as Q30, but coarser grain spectrum**) 2nd layer is sodium silicate (water-glass = Wg) with the modulusstated; coating amount in wt. %. The 2nd layer was prepared using sodiumwater-glass with a concentration of 10 wt. % (examples E1 to E8)***) In E5 and E6 the same starting substance and the same watersolution were employed, but the coating was carried out on thelaboratory scale in E6 and in a pilot plant in E5. The smooth surface ofE6 compared with E5, detectable by means of SEM photographs, is probablyresponsible for the increased stability of E6.#) The coating layer of water-glass was prepared in E9 as in examples E1to E8 using a 10 wt. % water-glass solution; the layer of E10 wasprepared using a 5 wt. % water-glass solution with the same modulus (Wg3.4).##) Before application of the coating layers, the fines content with<0.4 mm grain size was separated off by sieving.c) Determination of the Bleaching Activity

To determine the bleaching activity, standardized cotton test fabricwith staining by tea (WFK CFT PC/BC1) and red wine (EMPA 114) togetherwith 3 kg of laundry were washed in a commercially available drummachine at a washing temperature of 30° C. A mixture of 50 g base recipefrom table 1, 11.25 g sodium percarbonate and 4.14 g TAED was employedas the liquid detergent. The bleaching action was determined bydetermining the increase in reflectance of the washed test fabric at 457nm. (xenon lamp, UV barrier filter 420 nm, ceramic white standard fromDatacolor) as the mean from 5 washing experiments. The results of thewashing experiments are summarized in table 3. The experiment numbers ofthe detergent compositions according to the invention correspond to theexperiment numbers in table 2. TABLE 3 Bleaching action of liquiddetergents comprising sodium percarbonate % increase in % increase inEx. Sodium reflectance reflectance No. percarbonate tea stains red winestains CE2 Q35 8.5 21.8 E7 Q35/1.5%  5.7 19.5 Wg 3.3 E9 Q35/0.75% 6.820.3 Wg 3.4 E10 Q35/0.75% 6.3 20.4 Wg 3.4 CE3 none 0.8 12.3

1-15. (canceled)
 16. A liquid detergent and cleaning agent compositioncomprising a liquid medium with a water content of up to 15 wt %, basedon the composition, and particles of bleaching agent suspended in saidliquid medium, wherein each particle has a coating surrounding saidbleaching agent, said coating being comprised of at least two layers: a)an innermost layer, comprising one or more hydrate-forming inorganicsalts as the main component(s), and wherein said innermost layer makesup 2 to 20 wt % of the particle of coated bleaching agent; and b) anouter layer, which comprises as its main component(s), alkali metalsilicate(s) with a modulus of SiO₂ to M₂O (M=alkali metal) of greaterthan 2.5, and wherein said outer layer makes up 0.2 to 5 wt % of theparticle of coated bleaching agent, and wherein the dissolving time ofsaid particles of bleaching agent is at least 5 minutes, as measured for95% dissolution in water at 15° C. and 2 g/l.
 17. The composition ofclaim 16, wherein said bleaching agent is an inorganic or organic peroxycompounds.
 18. The composition of claim 16, wherein said bleaching agentcomprises sodium percarbonate.
 19. The composition of claim 16, whereinsaid bleaching agent comprises a peroxycarboxylic acid with one or twoperoxy groups.
 20. The composition of claim 16, wherein the innermostlayer of said coating consists essentially of one or more salts selectedfrom the group consisting of: alkali metal sulfates; magnesium sulfate;alkali metal carbonates; alkali metal bicarbonates; mixed salts ofsodium carbonate with sodium bicarbonates or with sodium sulfate; alkalimetal borates; and alkali metal perborates.
 21. The composition of claim16, wherein the outer layer of said coating consists essentially of 0.2to less than 3.0 wt % alkali metal silicate with a modulus in the rangeof from 3 to
 5. 22. The composition of claim 16, wherein the outer layerof said coating is prepared using an aqueous solution with an alkalimetal silicate content of 20 wt % or less.
 23. The composition of claim16, wherein said composition comprises 2 to 50 wt % of said particles ofbleaching agent and wherein the dissolving time of said particles ofbleaching agent is in the range of from 10 to 60 minutes.
 24. Thecomposition of claim 16, wherein said bleaching agent is a coatedinorganic peroxy salt and said composition further comprises an activeamount of a bleaching activator.
 25. The composition of claim 24,wherein said bleaching activator has a coating of one or more layerswhich reduces the rate of solution.
 26. The composition of claim 16,wherein said liquid medium comprises: one or more anionic and/ornonionic surfactants; water; a mono- or polyhydric alcohol having up to6 C atoms and which can optionally contain further hydrophilicsubstituents; and, optionally, a stabilizer which is capable of forminga chelate complex.
 27. The composition of claim 16, further comprisingone or more washing- and/or cleaning-active enzymes.
 28. The compositionof claim 16, wherein said composition is packaged in portioned form inbags of a water-soluble polymeric material which are suitable forwashing and cleaning purposes.
 29. The composition of claim 16, furthercomprising an active amount of an opacifying agent selected from eitherstyrene-acrylic copolymers or silicone-quats.
 30. The composition ofclaim 16, wherein said composition comprises sodium percarbonate with anaverage particle diameter in the range of from 0.5 to 1 mm andsubstantially no particles of bleaching agent smaller than 0.2 mm. 31.The composition of claim 16, wherein said particles of bleaching agentcomprise sodium percarbonate and wherein the content of particles with adiameter of less than 0.4 mm is less than 10 wt % of said bleachingagent.